The thermo-electric generator is a kind of generator made on the basis of temperature differences, and the heat energy is transformed into electric energy due to Seeback effect. The working principle of thermo-electric generator is that connecting one end of two different metals or two different types of thermo-electric conversion materials P-type and N-type semiconductors, placing this end in high temperature condition, and placing the other end in low temperature condition. Compared with the other end, the end in high temperature condition has better thermal activation and higher density of electrons and holes, and the electrons and holes spread to the end in low temperature condition, such that an electric potential difference is formed in the end in low temperature condition. Combining a number of this kind of thermo-electric conversion materials P-type and N-type semiconductors to form a module supplying adequate voltage, this module becomes a thermo-electric generator.
The thermo-electric generator is a kind of clean, noiseless energy without discharging any hazardous substance, having high reliability and long useful time, and supplying long, safe and continuous table electricity output. Presently the thermo-electric generator is made by cutting and welding the thermo-electric materials. There are two types of fabrication methods. In the first method, a photosensitive resist is painted on the same chip, then P-type and N-type areas are formed through double photo etching respectively, and finally P-type and N-type thermo-electric materials are deposited in the P-type and N-type area respectively. This method is difficult for application, especially for the procedure of combining thermo-electric units in which the chip is required to be stripped from the deposited thermo-electric units. In the second method, P-type and N-type thermo-electric unit chips are separately manufactured. In the fabrication of micro thin-film thermo-electric generator, the conducting layer connecting P-type and N-type thermo-electric units can be manufactured assuming that the chip is not stripped from the deposited thermo-electric units. This method has complicated procedures. The thin-film of the thermo-electric generator is merely limited to single thin-film connecting P-type and N-type thermo-electric units, and then the performance is limited.